Blockchain-Based CP-ABE with Publicly Verifiable Outsourced Decryption in IoT

Attribute based encryption (ABE) was used to ensure confidentiality and access control in IoT as a preeminent cryptographic primitive. However, the traditional ABE with outsourced decryption cannot achieve public verifiability for decryption results. In this paper, blockchain technology is appplied to realize the publicly verifiability in our CP-ABE scheme. Furthermore, our scheme has many characteristics: white box traceability, malicious users revocability and updatability of ciphertext. Lastly, we present the security analysis and demonstrate the performance of our scheme. The results show that our scheme is IND-CPA secure under the standard model and also has high efficiency.